THE HUMERUS 



11" 



the groove into a canal. In addition to the long tendon of the biceps and its tube 

 of synovial membrane, the groove transmits a branch of the anterior circumtlex 

 artery. The constriction immediately below the tuberosities is the surgical neck. 

 The shaft is prismatic in its upper third, but flattened below. Three borders 

 and three surfaces may be recognised. The anterior border commences at the 



Fig. 124.— The Left Humerus. (Posterior view.) 



Capsular ligament 

 Infra-spinatua 



Teres minor ■ 



Triceps 'external head 



MUSCULO-SPIRAL GROOVE • 



Triceps (internal head) . 



Capsular ligament 



OLECRANON FOSSA . 



EXTERNAL CONDYLE 

 Anconeus and external lateral ligament 



;\'|^_ INTERNAL CONDYLE 



»:1 ~ 



GROOVE FOR ULNAR NERVE 

 Flexor carpi ulnaris 



greater tuberosity, as the anterior or outer lip of the bicipital groove, and, passing 

 do\mwards, skirts the radial side of the coronoid fossa, to become continuous with 

 the ridge separating the capitellum and trochlea. The radial or outer border 

 extends from the posterior border of the greater tuberositv to the radial condyle. 

 This border is not well marked in the upper part of the shaft; near the middle it is 



